I do not know if I can help, but I have also running OCPN v1.3.6 with Mac OS X v10.6.4. I use a Royaltek GPS Bluetooth mouse which runs fine with OCPN. What kind and brand of GPS device do you have? If it is an USB device it seems you must have an USB driver for Mac OS X. Does the manufactorer provide such a driver?

Hi Carcode,
many thanks for your reply, I have a BU-353 USB GPS navigation Receiver, I have installed the driver supplied by the manufacturer, when I look at the USB infos on Mac, I can see the driver but I don't know how to configure OpenCPN to recognize the GPS, I don't have any COM port to communicate as it is the case in Windows... I am completely new on MAC OS... this does not help!!!

The USB driver should provide a virtual serial com port. For my Bluetooth GPS mouse it is: /dev/cu.BlueGPS284785-SerialPort
This is entered into "NMEA Data Source" in the settings for GPS for OCPN.

I am sorry not to have an USB GPS device to write you the whole story about installing a virtual com port with an USB device. Be sure also that the virtual com port has the settings 8/N/1 and 4800 baud. These are the settings of the needed serial protocol for NMEA-0183, otherwise data transfer does not work.

If your GPS installation runs, you will see the GPS data on the left side of the status bar at the bottom of OCPN if "Show Status Bar" is activated in the settings.

Hi CarCode, maybe you can help me, or anyone else. I run OCPN 2.5 on a MacBookPro, OS X 10.6.7 in one disk partition, and on Windows in the second partition. It runs smoother on Windows, I must admit (toolbar, route manager). Today I connected it to my handheld GPSmap 60CSx. On windows it worked rightaway, on OS X still no connection. The reason probably is that I am not able to write Garmin in the NMEA Data Source (on Windows "Garmin" is already in the menu and I can select it). On OS X I can write it manually, but next time I open it there is nothing there anymore. Would you know what I do wrong? For about everything else I do on the Mac I prefer OS X, so it would be nice to get navigation working too.

It is not possible this way to use the GPS puck for more then one program at at time. That is to use the puck for OpenCPN the Globalsat utility program must be closed.

To use several programs with the GPS data of the puck at the same time you have to install the gpsd daemon. But this is another question and only useful for users with some more experience.

To come back to your current problem it might be useful to check the name of the com port first. So when the puck is connected to the MacBook please open the Terminal program to be find in the /Applications/Utilities/ folder. There you enter the command:
ls /dev/cu.* (That are letters L and S, space and then /dev/cu.*)
and return with the Enter key.
The available com ports on your system should be the result.
Try any of the shown ports. I don't know the correct one because I don't have a Globalsat. But if the Globalsat Utility works, openCPN should work as well. You might have to wait also 1-2 minutes after a cold restart of the puck to give him time to find the satellits.

Opened OpenCPN/Options/Connections, deleted the previous configured connection to start fresh with a new one: selected Serial, for Dataport the down arrow showed the 2 ports reported in Terminal, I selected /dev/cu.usbserial (The one that worked previously with the Globalsat utility), Baudrate = 4800, Protocol = NMEA 0183, Priority = 1 and Control checksum = √.

To be sure it is not a problem of OPenCPN you can try another program.Polar Navy - Marine Navigation Software is free for testing and is using /dev/tty.* instead of /dev/cu.* but this should make no difference:

My puck may take up to 15 minutes from a COLD START TO SEND DATA to either the app or OCPN.

If your puck takes 15 minutes from cold start to have a fix then send it back to the seller and claim it. A puck should have a fix from cold start within a minute. My puck takes 35 secs from cold start, 33 secs from warm start and 1 sec from hot start (specified by the factory).